Hey man, i was in a similar predicament a couple weeks ago. I know its a tough choice because civil engineering is the more interesting of the two subjects, however you have to consider whether you'll be able to get a job once you finish the degree. Quantity surveying there is definitely a shortage of them, but im sure its for good reason, you have to either really enjoy it, or be willing to work for money and money alone. you say a company is looking to hire you as a qs and reward you well (pay, car, uni), It would be the obvious choice if you enjoyed both equally, but QSing just isnt as interesting as Civil engineering.
Ive decided to apply for all engineering courses as id really rather be in a job i somewhat enjoy than one id be bored in.
I know people say theres always a demand for civil engineers, but really what they mean is experienced engineers.
A company is looking to take you in now. it really is a gamble for your future, mate. Be a qs and have guaranteed job, no debt, and maybe enjoy itor maybe not. Study engineering, have debt, find a job.
Final thing i will say is: 5 years experience QSing will help you to become a project manager or chief engineer as you know all about the tendering, pricing and legal side of construction, so if you dont like the QSing you could then study engineering after and have a higher chance of success at that. Although if you can get into a top top (top top) university for engineering, then youd probably be set too.
its a tough choice man.